Headlamps which illuminate the roadway section lying in front of the automobile and which adapt the illumination during driving, are being increasingly widely used, especially in new and high-quality automobiles. With these headlamps, the emitted light is not only emitted straight in front or in a fixed direction, but the headlamp, in particular its reflector, is designed in such a manner that during cornering, areas located obliquely in front of the automobile can also be illuminated to avoid colliding with a non-illuminated obstacle in the bend. To this end, a light cone emanating from the headlamp is pivotable or rotatable about a substantially vertically aligned yaw axis. It is hereinafter implied that either the entire headlamp or only a part thereof, such as the reflector for example, or only a lamp inside the reflector, is turned to obtain different directions of emission.
For turning the headlamp, a controller is provided which can be integrated in a central controller of the automobile, wherein, inter alia, signals relating to the vehicle speed and/or a steering-lock angle, which determines the radius of the bend being negotiated, can be fed to the controller. These signals can be used by the controller to calculate the optimum pivot angle of the headlamp for the best possible illumination and an electrical adjusting motor, for example, can be correspondingly driven.
Known from EP 1 354 761 A2 is a device for controlling a cornering light headlamp, which has an additional yaw rate sensor and a transverse acceleration sensor in order to drive turning of the headlamp by means of these sensor signals. Thus, however, additional sensors are required in the automobile or on the headlamp.
The known headlamps are disadvantageous insofar as when the headlamp is driven by means of the steering-lock angle as well as the vehicle speed, in particular during short and rapid steering movements which result in virtually no change in the direction of travel, the headlamps are turned nevertheless, with the result that when negotiating a bend, areas of the roadway are inadequately illuminated. In addition, during understeering of the automobile, the effect may arise that the headlamps illuminate too far into the inside of the bend and the outer edge of the roadway is not sufficiently illuminated. If the vehicle is oversteering, the opposite effect occurs.
It is at least one object of the invention to provide a headlamp of the type specified initially, where uniform illumination of the roadway is ensured even when negotiating a bend at speed. In addition, other objects, desirable features, and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.